Maribacter halichondriae sp. nov., isolated from the marine sponge Halichondria panicea, displays features of a sponge-associated life style

A new member of the family Flavobacteriaceae (termed Hal144T) was isolated from the marine breadcrumb sponge Halichondria panicea. Sponge material was collected in 2018 at Schilksee which is located in the Kiel Fjord (Baltic Sea, Germany). Phylogenetic analysis of the full-length Hal144T 16S rRNA gene sequence revealed similarities from 94.3 to 96.6% to the nearest type strains of the genus Maribacter. The phylogenetic tree of the 16S rRNA gene sequences depicted a cluster of strain Hal144T with its closest relatives Maribacter aestuarii GY20T (96.6%) and Maribacter thermophilus HT7-2T (96.3%). Genome phylogeny showed that Maribacter halichondriae Hal144T branched from a cluster consisting of Maribacter arenosus, Maribacter luteus, and Maribacter polysiphoniae. Genome comparisons of strain Maribacter halichondriae Hal144T with Maribacter sp. type strains exhibited average nucleotide identities in the range of 75-76% and digital DNA-DNA hybridisation values in the range of 13.1-13.4%. Compared to the next related type strains, strain Hal144T revealed unique genomic features such as phosphoenolpyruvate-dependent phosphotransferase system pathway, serine-glyoxylate cycle, lipid A 3-O-deacylase, 3-hexulose-6-phosphate synthase, enrichment of pseudogenes and of genes involved in cell wall and envelope biogenesis, indicating an adaptation to the host. Strain Hal144T was determined to be Gram-negative, mesophilic, strictly aerobic, flexirubin positive, resistant to aminoglycoside antibiotics, and able to utilize N-acetyl-β-D-glucosamine. Optimal growth occurred at 25-30 °C, within a salinity range of 2-6% sea salt, and a pH range between 5 and 8. The major fatty acids identified were C17:0 3-OH, iso-C15:0, and iso-C15:1 G. The DNA G + C content of strain Hal144T was 41.4 mol%. Based on the polyphasic approach, strain Hal144T represents a novel species of the genus Maribacter, and we propose the name Maribacter halichondriae sp. nov. The type strain is Hal144T (= DSM 114563T = LMG 32744T).

Biomolecular Condensation: A New Phase in Cancer Research

Multicellularity was a watershed development in evolution. However, it also meant that individual cells could escape regulatory mechanisms that restrict proliferation at a severe cost to the organism: cancer. From the standpoint of cellular organization, evolutionary complexity scales to organize different molecules within the intracellular milieu. The recent realization that many biomolecules can "phase-separate" into membraneless organelles, reorganizing cellular biochemistry in space and time, has led to an explosion of research activity in this area. In this review, we explore mechanistic connections between phase separation and cancer-associated processes and emerging examples of how these become deranged in malignancy.

SIGNIFICANCE

One of the fundamental functions of phase separation is to rapidly and dynamically respond to environmental perturbations. Importantly, these changes often lead to alterations in cancer-relevant pathways and processes. This review covers recent advances in the field, including emerging principles and mechanisms of phase separation in cancer.